80km MPFI Conversion test - FAIL - Ford Forums - Mustang Forum, Ford Trucks, Ford Focus and Ford Cars

Sundeep · 02-26-2003, 17:57

Hey Guys,

Yesterday took the EA out for a long drive in the heat for the first time since the conversion. We did stop start driving in traffic and highway driving too.

Anyway, at some times it ran fine. Idling properly and taking off smoothly. But most of the time when put in first or second, the car jerked almost violently until the RPM rised to around 2000. At the same time the idle was a bitch too, going up to 900 and then coming down to 0 and going back up.

Now I haven't changed to the MPI fuel pump yet, but I am thinking the fuel pressure wouldn't be the cause as it was fine sometimes and crap the next.

Give me all your ideas please :(

Sundeep

SiX_iN_a_RoW · 02-26-2003, 18:04

perhaps a dirty ISC?
Im having troubles with an off idle hesitation....waiting to see if changing to the correct dizzy will sort it out

carazy · 02-26-2003, 18:27

have fun with the MPFI dizzy.
I stuffed around with my timing for ages with the MPFI dizzy and no matter how well it was setup the bastard would skip and miss badly.
If i set the timing completly wrong on the MPFI it would work correctly and would cain along but it would jerk just off idle and ping a little bit when you tromped it.
I've since installed the CFI one again and it started ok but still jerks and pings a little.
I'm going to set the base idle and timing again tonight and see if it works ok with the CFI distributor.
I get the feeling the problem relates to something else (differant ECU relay maybe??)
Diagnostic reveals no errors at all and my ISC is working correctly.
The only thing I have noticed is that when I let go of the throttle the revs stay up then drop back down slowly.(ISC??)
It's a hard life I tell you and I wouldn't recommend this job to anyone.
If anyone out there is considering purchasing a CFI falcon then converting it. DON'T! For god sake it's easier to get a good MPI auto and convert to manual or something.

Brent79 · 02-26-2003, 18:37

Remember when changing the dizzy that the positioning of it on MPI models is different to TBI. The TFI module on the CFI faces towards the rear of the engine and on MPI it faces towards the front. carazy, i had the same trouble about 12 months ago.. my car would start and run (no power) and after it warmed up it would go spacko, jumping rpm and spluttering for about 2 mins, then it would settle down again. Turned out that the SPOUT signal somehow made its way back into the ECU via the O2 input... hmmm (not my doing) - once all yer wiring and dizzy are sorted, you will be right! If fuel pressure was the only problem, it would show up different symptoms, flat spots and even stalling...

Brent

carazy · 02-26-2003, 21:55

see the thing is that the car returns no error messages at all.
Since fixing the ISC the codes are 11 10 11.
I know the way the dizzy's sit is differant.
I've got it running near on perfect with the CFI dizzy I just need to tune it up and it should be right.
If I can't get it perfect to night it goes to the mech on sat.
He's the king of Ford so he'll fix it.

NZ · 02-27-2003, 00:23

Quote:

Originally posted by Brent79
Remember when changing the dizzy that the positioning of it on MPI models is different to TBI. The TFI module on the CFI faces towards the rear of the engine and on MPI it faces towards the front.

Brent

As long as when you set it up the engine is on TDC intake stroke and the dizzy has the rotor mark lined up with the notch on the case of the dizzy the actual position of the tfi doesnt matter. But it is preferable to have it away from the engine as far as possible.

carazy · 02-27-2003, 02:38

bwahahahahah my car runs perfect now with the following changes:
Injector loom, manifold, ECU, ED fuel pump, ISC wire change and CFI distributor.
I always thought I was doing it wrong with the timing but for some reason my car just doesn't like the MPFI one.
I think that if you change the indash loom you need the MPFI one and if you wire the ISC you just need the CFI one. Oh well I don't care why it works it just does.

Sundeep · 02-27-2003, 03:10

Can I have some help now :(

I had a friend give it a work out and I found out one more thing on top of the rest, it's got no power in third.

Any ideas?

Sundeep

carazy · 02-27-2003, 14:50

dude if you havn't changed the fuel pump then do it!!!
I would say that would be one of the problems.
The think I learnt from my convertion is that every part has a reason for being there.
The locking ring on the fuel pump is a total bitch btw I suggest you do as the Ford dealers do buy a new ring and break the old one off.

SiX_iN_a_RoW · 02-27-2003, 17:11

Yeah, We had to remove the fuel tank to get the ring off, it just wouldnt budge! the one we took off at the wreckers was a hell of alot easier though!
Well ive ALMOST sorted my car out, still have a slight hesitation off idle but its a vast improvement over what it was like, its safe to pull out in traffic now!
I have a feeling theres still a slight vacuum leak somewhere, also im not sure how healthy this MPFI fuel pump is, tried everything but its still noisy as hell.

Sundeep have you tried adjusting the base timing? its possible you didnt tighten the hold-down bolt enough and its worked its way loose...happens to me all the time, crappy NSW roads :(
Also check if the manifold bolts have come loose due to the heat of the engine, always should re-tension them after running the engine when installing any new gasket